husband denies for registering our marriage

I am an Architect from tamilnadu I am working and I got married to a B.E degree holder. Ours is a arranged marriage and we got married in 2012. Since then my husband gives some excuse for doing marriage registration. first me and my family thought he was busy in is job so he didn't have time. But now I told him that I need to update my martial status in my passport for which I require marriage registration certificate. Now also he says he will see to that latter. my dad asked him to make this priority and cornerd him, now he is trying to avoid us. His parents also supports him and says we will do it later. me and my husband had many problems in between, he drinks alcohol all most everyday and this habit of his was hidden to us before marriage. His family also encourages him on this habit So I am in my mother's house since 2 yrs with my 1.5 yrs old girl baby in the same town. He doesn't take any responsibility on me and my baby. he has not spent anything for me and my baby so far. I have a doubt that he might have had an affair with someone in his early life and would have done register marriage. so I have planed to send him a notice through an advocate asking my husband to give reason for his denial for registration. And also to do all the legal procedures like getting us a ration card for address proof and also to give cash every month for baby's expenditures. Plz guide me what should I do.